Helena Mitasova | North Carolina State University (original) (raw)

Talks by Helena Mitasova

Brendan Harmon, North Carolina State University, presents the fascinating research that he, and c... more Brendan Harmon, North Carolina State University, presents the fascinating research that he, and co-authors, Helena Mitasova and Anna Petrasova, are conducting using "tangible GIS," a process that seamlessly links the digital processes of GIS, geographic simulations, and CAD-CAM with the more intuitive processes of analog design in a generative cycle. Topics include Kinect 3D scanning, 3D printing, CNC routing, human computer interaction, tangible user interfaces, spatio-temporal modeling, & open source GIS.

Papers by Helena Mitasova

ISPRS International Journal of Geo-Information

Visual characteristics of urban environments influence human perception and behavior, including c... more Visual characteristics of urban environments influence human perception and behavior, including choices for living, recreation and modes of transportation. Although geospatial visualizations hold great potential to better inform urban planning and design, computational methods are lacking to realistically measure and model urban and parkland viewscapes at sufficiently fine-scale resolution. In this study, we develop and evaluate an integrative approach to measuring and modeling fine-scale viewscape characteristics of a mixed-use urban environment, a city park. Our viewscape approach improves the integration of geospatial and perception elicitation techniques by combining high-resolution lidar-based digital surface models, visual obstruction, and photorealistic immersive virtual environments (IVEs). We assessed the realism of our viewscape models by comparing metrics of viewscape composition and configuration to human subject evaluations of IVEs across multiple landscape settings. We...

Drones

Deriving crop information from remotely sensed data is an important strategy for precision agricu... more Deriving crop information from remotely sensed data is an important strategy for precision agriculture. Small unmanned aerial systems (UAS) have emerged in recent years as a versatile remote sensing tool that can provide precisely-timed, fine-grained data for informing management responses to intra-field crop variability (e.g., nutrient status and pest damage). UAS sensors with high spectral resolution used to compute informative vegetation indices, however, are practically limited by high cost and data dimensionality. This research extends spectral analysis for remote crop monitoring to investigate the relationship between crop health and 3D canopy structure using low-cost UAS equipped with consumer-grade RGB cameras. We used flue-cured tobacco as a case study due to its known sensitivity to fertility variation and nutrient-specific symptomology. Fertilizer treatments were applied to induce plant health variability in a 0.5 ha field of flue-cured tobacco. Multi-view stereo images f...

ISPRS International Journal of Geo-Information

All over the world, organizations are increasingly considering the adoption of open source softwa... more All over the world, organizations are increasingly considering the adoption of open source software and open data. In the geospatial domain, this is no different, and the last few decades have seen significant advances in this regard. We review the current state of open source geospatial software, focusing on the Open Source Geospatial Foundation (OSGeo) software ecosystem and its communities, as well as three kinds of open geospatial data (collaboratively contributed, authoritative and scientific). The current state confirms that openness has changed the way in which geospatial data are collected, processed, analyzed, and visualized. A perspective on future developments, informed by responses from professionals in key organizations in the global geospatial community, suggests that open source geospatial software and open geospatial data are likely to have an even more profound impact in the future.

ISPRS International Journal of Geo-Information

Accurate information on the number and distribution of pedestrians in space and time helps urban ... more Accurate information on the number and distribution of pedestrians in space and time helps urban planners maintain current city infrastructure and design better public spaces for local residents and visitors. Previous studies have demonstrated that using webcams together with crowdsourcing platforms to locate pedestrians in the captured images is a promising technique for analyzing pedestrian activity. However, it is challenging to efficiently transform the time series of pedestrian locations in the images to information suitable for geospatial analytics, as well as visualize data in a meaningful way to inform urban design or decision making. In this study, we propose to use a space-time cube (STC) representation of pedestrian data to analyze the spatio-temporal patterns of pedestrians in public spaces. We take advantage of AMOS (The Archive of Many Outdoor Scenes), a large database of images captured by thousands of publicly available, outdoor webcams. We developed a method to obta...

Tangible Modeling with Open Source GIS, 2015

Tangible Modeling with Open Source GIS, 2015

Earth Surface Processes and Landforms, 2015

ABSTRACT Streambank erosion is a primary source of suspended sediments in many waterways of the U... more ABSTRACT Streambank erosion is a primary source of suspended sediments in many waterways of the U.S. Atlantic Piedmont. This problem is exacerbated where banks are comprised of fine sediment produced by the intensive land use practices of early European settlers. A stream in this region, Richland Creek incises into banks comprised of three stratigraphic layers associated with historic land use: pre-European settlement, early European agriculture and development, and water-powered milldam operation. This study aims to identify the bank processes along a reach of Richland Creek that is eroding towards its pre-disturbance elevation. The volume of material that has eroded along this stream since the milldam breached was calculated by differencing a reconstructed surface of the pond bed and an aerial lidar digital terrain model (DTM). Immediately downstream from the study reach, the channel is floored by bedrock and immediately upstream the rate of channel erosion approximately doubled along the longitudinal profile of Richland Creek, which indicate that the study reach spans the transition from a channel dominated by vertical incision in the upstream direction to horizontal widening in the downstream direction.The combined hydrometeorological conditions and dominant processes causing reach-scale cut bank erosion were investigated with analyses of stream stage, precipitation, and streambank volumetric and surfaces change that was measured during nine terrestrial lidar surveys in 2010–2012. The spatial variability of erosion during a simulated precipitation event was examined in a field-based experiment. Erosion was greatest where mill pond sediment columns detached along vertical desiccation and horizontal seepage cracks. This sediment accumulated on the bank toe throughout the study and was a source of readily-entrained fine sediment contrary to the upper reaches where depositional accommodation space is more limited. Findings suggest that hotspots of sediment excavation progress upstream, indicating that restoration efforts should focus upon stabilizing banks at these locations. This article is protected by copyright. All rights reserved.

ISPRS International Journal of Geo-Information, 2015

Water Science and Technology Library, 2005

To support a number of projects focused on diverse biological and physical science aspects of the... more To support a number of projects focused on diverse biological and physical science aspects of the upper Río Chagres basin, a detailed stream network was extracted from digital elevation data obtained by interferometric radar survey. The elevation data represented the bald earth surface plus a forest canopy of varying height. Therefore, different algorithms for stream network extraction were qualitatively evaluated in terms of their capability to extract accurate stream locations from this challenging type of elevation data. The programs based on a shortest path algorithm and an imposed gradients constraint provided stream locations that were closer to on-ground GPS measurements than the tools based on depressions filling and iterative linking. The influence of different spatial resolutions on network structure and orientation was also explored.

SpringerBriefs in Computer Science, 2014

SpringerBriefs in Computer Science, 2014

SpringerBriefs in Computer Science, 2014

Management of highly dynamic coastal landscapes requires repeated mapping and analysis of observe... more Management of highly dynamic coastal landscapes requires repeated mapping and analysis of observed changes. Modern mapping techniques such as lidar increased the frequency and level of detail in coastal surveys and new methods were developed to extract valuable information from these data using Geographic Information Systems. The brief presents techniques for analyzing and visualizing coastal topographic and shoreline change and sand dune dynamics using open source GRASS GIS.

Treatise on Geomorphology, 2013

ABSTRACT This chapter explains the theory and methods for GIS-based modeling of soil erosion, sed... more ABSTRACT This chapter explains the theory and methods for GIS-based modeling of soil erosion, sediment transport, and deposition by surface water flow. The mathematical foundations of erosion models are introduced and simplified equations, suitable for GIS implementation, are derived. The presented methods cover modeling of hillslope erosion and deposition, gully formation, and landscape evolution processes. Coupling of erosion models with GIS is discussed, followed by examples of GIS implementation of simple and advanced models. The concepts and methods are illustrated using two case studies, that focus on feedbacks between the human activity and landscape processes.

Brendan Harmon, North Carolina State University, presents the fascinating research that he, and c... more Brendan Harmon, North Carolina State University, presents the fascinating research that he, and co-authors, Helena Mitasova and Anna Petrasova, are conducting using "tangible GIS," a process that seamlessly links the digital processes of GIS, geographic simulations, and CAD-CAM with the more intuitive processes of analog design in a generative cycle. Topics include Kinect 3D scanning, 3D printing, CNC routing, human computer interaction, tangible user interfaces, spatio-temporal modeling, & open source GIS.

ISPRS International Journal of Geo-Information

Visual characteristics of urban environments influence human perception and behavior, including c... more Visual characteristics of urban environments influence human perception and behavior, including choices for living, recreation and modes of transportation. Although geospatial visualizations hold great potential to better inform urban planning and design, computational methods are lacking to realistically measure and model urban and parkland viewscapes at sufficiently fine-scale resolution. In this study, we develop and evaluate an integrative approach to measuring and modeling fine-scale viewscape characteristics of a mixed-use urban environment, a city park. Our viewscape approach improves the integration of geospatial and perception elicitation techniques by combining high-resolution lidar-based digital surface models, visual obstruction, and photorealistic immersive virtual environments (IVEs). We assessed the realism of our viewscape models by comparing metrics of viewscape composition and configuration to human subject evaluations of IVEs across multiple landscape settings. We...

Drones

Deriving crop information from remotely sensed data is an important strategy for precision agricu... more Deriving crop information from remotely sensed data is an important strategy for precision agriculture. Small unmanned aerial systems (UAS) have emerged in recent years as a versatile remote sensing tool that can provide precisely-timed, fine-grained data for informing management responses to intra-field crop variability (e.g., nutrient status and pest damage). UAS sensors with high spectral resolution used to compute informative vegetation indices, however, are practically limited by high cost and data dimensionality. This research extends spectral analysis for remote crop monitoring to investigate the relationship between crop health and 3D canopy structure using low-cost UAS equipped with consumer-grade RGB cameras. We used flue-cured tobacco as a case study due to its known sensitivity to fertility variation and nutrient-specific symptomology. Fertilizer treatments were applied to induce plant health variability in a 0.5 ha field of flue-cured tobacco. Multi-view stereo images f...

ISPRS International Journal of Geo-Information

All over the world, organizations are increasingly considering the adoption of open source softwa... more All over the world, organizations are increasingly considering the adoption of open source software and open data. In the geospatial domain, this is no different, and the last few decades have seen significant advances in this regard. We review the current state of open source geospatial software, focusing on the Open Source Geospatial Foundation (OSGeo) software ecosystem and its communities, as well as three kinds of open geospatial data (collaboratively contributed, authoritative and scientific). The current state confirms that openness has changed the way in which geospatial data are collected, processed, analyzed, and visualized. A perspective on future developments, informed by responses from professionals in key organizations in the global geospatial community, suggests that open source geospatial software and open geospatial data are likely to have an even more profound impact in the future.

ISPRS International Journal of Geo-Information

Accurate information on the number and distribution of pedestrians in space and time helps urban ... more Accurate information on the number and distribution of pedestrians in space and time helps urban planners maintain current city infrastructure and design better public spaces for local residents and visitors. Previous studies have demonstrated that using webcams together with crowdsourcing platforms to locate pedestrians in the captured images is a promising technique for analyzing pedestrian activity. However, it is challenging to efficiently transform the time series of pedestrian locations in the images to information suitable for geospatial analytics, as well as visualize data in a meaningful way to inform urban design or decision making. In this study, we propose to use a space-time cube (STC) representation of pedestrian data to analyze the spatio-temporal patterns of pedestrians in public spaces. We take advantage of AMOS (The Archive of Many Outdoor Scenes), a large database of images captured by thousands of publicly available, outdoor webcams. We developed a method to obta...

Tangible Modeling with Open Source GIS, 2015

Tangible Modeling with Open Source GIS, 2015

Earth Surface Processes and Landforms, 2015

ABSTRACT Streambank erosion is a primary source of suspended sediments in many waterways of the U... more ABSTRACT Streambank erosion is a primary source of suspended sediments in many waterways of the U.S. Atlantic Piedmont. This problem is exacerbated where banks are comprised of fine sediment produced by the intensive land use practices of early European settlers. A stream in this region, Richland Creek incises into banks comprised of three stratigraphic layers associated with historic land use: pre-European settlement, early European agriculture and development, and water-powered milldam operation. This study aims to identify the bank processes along a reach of Richland Creek that is eroding towards its pre-disturbance elevation. The volume of material that has eroded along this stream since the milldam breached was calculated by differencing a reconstructed surface of the pond bed and an aerial lidar digital terrain model (DTM). Immediately downstream from the study reach, the channel is floored by bedrock and immediately upstream the rate of channel erosion approximately doubled along the longitudinal profile of Richland Creek, which indicate that the study reach spans the transition from a channel dominated by vertical incision in the upstream direction to horizontal widening in the downstream direction.The combined hydrometeorological conditions and dominant processes causing reach-scale cut bank erosion were investigated with analyses of stream stage, precipitation, and streambank volumetric and surfaces change that was measured during nine terrestrial lidar surveys in 2010–2012. The spatial variability of erosion during a simulated precipitation event was examined in a field-based experiment. Erosion was greatest where mill pond sediment columns detached along vertical desiccation and horizontal seepage cracks. This sediment accumulated on the bank toe throughout the study and was a source of readily-entrained fine sediment contrary to the upper reaches where depositional accommodation space is more limited. Findings suggest that hotspots of sediment excavation progress upstream, indicating that restoration efforts should focus upon stabilizing banks at these locations. This article is protected by copyright. All rights reserved.

ISPRS International Journal of Geo-Information, 2015

Water Science and Technology Library, 2005

To support a number of projects focused on diverse biological and physical science aspects of the... more To support a number of projects focused on diverse biological and physical science aspects of the upper Río Chagres basin, a detailed stream network was extracted from digital elevation data obtained by interferometric radar survey. The elevation data represented the bald earth surface plus a forest canopy of varying height. Therefore, different algorithms for stream network extraction were qualitatively evaluated in terms of their capability to extract accurate stream locations from this challenging type of elevation data. The programs based on a shortest path algorithm and an imposed gradients constraint provided stream locations that were closer to on-ground GPS measurements than the tools based on depressions filling and iterative linking. The influence of different spatial resolutions on network structure and orientation was also explored.

SpringerBriefs in Computer Science, 2014

SpringerBriefs in Computer Science, 2014

SpringerBriefs in Computer Science, 2014

Management of highly dynamic coastal landscapes requires repeated mapping and analysis of observe... more Management of highly dynamic coastal landscapes requires repeated mapping and analysis of observed changes. Modern mapping techniques such as lidar increased the frequency and level of detail in coastal surveys and new methods were developed to extract valuable information from these data using Geographic Information Systems. The brief presents techniques for analyzing and visualizing coastal topographic and shoreline change and sand dune dynamics using open source GRASS GIS.

Treatise on Geomorphology, 2013

ABSTRACT This chapter explains the theory and methods for GIS-based modeling of soil erosion, sed... more ABSTRACT This chapter explains the theory and methods for GIS-based modeling of soil erosion, sediment transport, and deposition by surface water flow. The mathematical foundations of erosion models are introduced and simplified equations, suitable for GIS implementation, are derived. The presented methods cover modeling of hillslope erosion and deposition, gully formation, and landscape evolution processes. Coupling of erosion models with GIS is discussed, followed by examples of GIS implementation of simple and advanced models. The concepts and methods are illustrated using two case studies, that focus on feedbacks between the human activity and landscape processes.

Encyclopedia of GIS, 2008

Management of highly dynamic coastal landscapes requires repeated mapping and analysis of observe... more Management of highly dynamic coastal landscapes requires repeated mapping and analysis of observed changes. Modern mapping techniques such as lidar increased the frequency and level of detail in coastal surveys and new methods were developed to extract valuable information from these data using Geographic Information Systems. The brief presents techniques for analyzing and visualizing coastal topographic and shoreline change and sand dune dynamics using open source GRASS GIS.

This book presents a new type of modeling environment where users interact with geospatial simula... more This book presents a new type of modeling environment where users interact with geospatial simulations using 3D physical models of studied landscapes. Multiple users can alter the physical model by hand during scanning, thereby providing input for simulation of geophysical processes in this setting.
The authors have developed innovative techniques and software that couple this hardware with open source GRASS GIS, making the system instantly applicable to a wide range of modeling and design problems. Since no other literature on this topic is available, this Book fills a gap for this new technology that continues to grow.
Tangible Modeling with Open Source GIS will appeal to advanced-level students studying geospatial science, computer science and earth science such as landscape architecture and natural resources. It will also benefit researchers and professionals working in geospatial modeling applications, computer graphics, hazard risk management, hydrology, solar energy, coastal and fluvial flooding, fire spread, landscape, park design and computer games.